July 12, 2001 The Associated Press
Cells that prompt formation of scar tissue may play a major part in the rejection of transplanted kidneys, a study found.
It is the first indication that the body's normal reaction to wounds, rather than to the donor cells, may cause kidney rejection, according to Dr. Paul Grimm of the University of California-San Diego School of Medicine.
He and colleagues at the University of Manitoba and the University of Pennsylvania analyzed tissue samples from 14 patients suffering from chronic rejection.
Chromosomal tracking showed that the patients' bodies were the source of one-quarter or more of the mesenchymal cells - scar-creation cells - in the tissues around each new kidney, they reported in Thursday's New England Journal of Medicine.
This suggests that precursors of mesenchymal cells - scar-building cells - circulate in the blood, settling in and colonizing damaged areas, Grimm said.
"We don't know why on some occasions the repair leads to perfect healing, but other times the repair is imperfect leading to the chronic scarring that is part of rejection," Grimm said.
Scarring constricts blood vessels leading to the kidney, making it fail prematurely.
If ways can be found to block the scar-building cells, it might be possible to reduce or prevent kidney rejection, the researchers said.
"These findings open the door to a room of transplant medicine we've never seen before," Grimm said. "We can now possibly find ways to block these scar-causing cells by shutting down the signals that activate them in the first place."
Copyright 2001 The Associated Press. All rights reserved.
